查询词典 racemization

L-Glutamic acid racemization research is of great importance for the preparation of optical pure D-Glu.

L-谷氨酸消旋化反应对于制备光学纯D-谷氨酸具有重要的意义。

Amino acid racemization dating of Holocene shell deposits from coastal area of Fujian［J］.

福建沿海全新世贝壳沉积物的氨基酸外消旋年代测定［J］。

Racemization is the conversion of an optical ly active form of a compound into a racemic mixture; reversing this process is called resolution.

外消旋作用是把一种化合物的光学活性形式转化为外消旋的混合物；这个过程的逆过程称为拆分。

The racemization reactions were found to follow apparent first order kinetics.

发现其消旋反应属於显见一级动力学过程。

By ~(31)P NMR, it was found that the racemization of amino acids was minimized. And it seams that L-amino acid has different reaction acticity from the D-amino acids.

其次，从磷化学的角度研究了氨基酸的立体化学对酯交换反应的结构效应，发现了以磷酰基保护的氨基酸以及含磷缩合试剂的方法进行多肽的合成，氨基酸消旋现象很少发生。

The influences of the type and dosage of the aldehyde, organic acids, as well as the water content in the reaction system on the racemization were examined in detail, and L-Glu was racemized quickly in the presence of 0.2 molar ratio of L-Glu to salicylaldehyde in acetic acid containing 20% water.

详细考察了醛的种类及用量、羧酸溶剂的种类、反应体系的含水量对消旋化的影响，结果表明L-谷氨酸在含20%水的乙酸溶剂中，以水杨醛作为催化剂(水杨醛与L-谷氨酸的物质的量比为0.2)的优化条件下可以快速地被消旋化。

Among these immoniumsalts, HOBt-based reagents were proved to be superior to the corresponding uroniumsalts in both reactivity and racemization.

其中HOBt衍生的亚胺正离子型缩合剂无论在反应活性还是在产物光学纯度方面都大大优于脲正离子型缩合剂。

Racemization is found with optically active substrates.

发现旋光基质有外消旋作用。

By using on-lined pyrolyzer-chiral MDGC/NPD,it was found that,racemization of S--nicotine reagent was highly synchronous to its thermal degradation process.

采用在线裂解-chiral-MDGC/NPD，发现S-尼古丁试剂的消旋化与热裂解进程具有高度的同步性。

A key feature of this methodology is the use of metal catalysts for the in situ racemization of enzymatically unreactive enantiomers in the enzymatic resolution of racemic substrates.

酶和金属配合物的结合扩展了这个方法的使用范围，该方法的主要特征是用酶催化拆分和金属催化原位外消旋化未反应的底物，克服了经典动力学拆分最高产率只有50%的缺陷。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。